In the mobile communications market, the number worldwide users and the increasing demand for a wide range of mobile services (e.g., including wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls, and mobile TV technologies) has driven the development of new generations of cellular standards having new frequency bands and higher data rates. To accommodate users on a variety of networks, one solution can be to particularly design mobile devices to be used with a specific network configuration. This approach can lead to manufacturing inefficiencies, however, as multiple variations of the same product would be needed to accommodate the multiple different mobile telecommunications standards.
As a result, it can be desirable for mobile devices to be compatible with more than one set of mobile telecommunications standards to provide manufacturing efficiency (e.g., 1 SKU for all global production) and device versatility. In particular, it is desirable for a mobile device to be able to operate within frequency bands associated with all of 2G (e.g., GSM/CDMA), 3G (e.g., EVDO/WCDMA), and 4G (e.g., LTE) technologies. In addition, further advancements in mobile technology (e.g., LTE, LTE-A, and 5G) will require additional expansions to the range of frequencies in which a mobile device will be expected to be operable. Furthermore, multiple antenna structures (e.g., MIMO, carrier aggregation) can be desired to provide additional functional advantages.
The ability to operate in such a wide range of frequencies can be limited, however, by the physical size of the wireless antenna. Especially in those systems that use multiple antennas in the mobile device, the amount of physical space required can be quite large. In addition, design constrains imposed by the continually shrinking size of modern mobile devices (e.g., slim, chic, curved, narrow bezel) can present a natural conflict with the volume needed to accommodate a multi-frequency antenna system. As a result, it would be advantageous to have an antenna system for advanced mobile technology that can better achieve a wide bandwidth with a small antenna volume.